Comparison of Metabolic Diversity of Meadow and Chestnut Tree Soil Samples Collected at Hurricane Creek Field Station

Researchers at the University of North Georgia’s Hurricane Creek Field Station are leading efforts in the area of ecological restoration, such as developing blight-resistant hybrids of the American Chestnut Tree (Castanea dentata). As seen in the literature, a diverse microbiome is needed to support the growth of new flora through their roles in nutrient cycling, nitrogen fixation, and decomposition. Thus, this study aimed to characterize the metabolic and functional diversity of the microbes in the meadow and Chestnut nursery soil. Based on the large quantities of organic detritus in the meadow, we hypothesized that the microbes in the meadow soil samples would have greater levels of metabolic diversity compared to the microbes in the Chestnut nursery soil samples. Soil cores were collected at a depth of 5cm and diluted to 10^-8 before plating on Tryptic Soy Agar (TSA) and Potato Dextrose Agar (PDA). Metabolic Diversity was tested using Biolog EcoPlates to measure carbon source utilization over a period of 120 hours. Finally, isolated TSA colonies were Gram-stained to characterize morphology. Colony-forming units per gram of soil were found to be 4.4 × 10⁶ CFUs on TSA and 1.7 × 10⁶ CFUs on PDA. Biolog readings demonstrated that the microbes in the meadow soil sample utilized 96% of the carbon sources compared to Chestnut nursery samples, where only 77% were utilized. These results demonstrate a higher level of functional diversity in the meadow soil that supports new plant growth. Understanding soil microbial diversity can guide practices for future ecological restoration efforts.